6-Chamber Bubbler Airlocks & Rubber Demijohn Bungs An essential part of kit for your homebrew. Designed specifically for homebrew. It lets the CO² pressure out without letting contamination back in. Just partially fill with water and you're done. The Bubbler is a standard size so fits all fermenters The Bung fits Standard Glass Demijohns Bung Size:- Top - 31mm - Base - 26mm
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